Surface mount device/integrated passive device on package or device structure and methods of forming

ABSTRACT

Package structures and methods of forming them are described. In an embodiment, a package structure includes an integrated circuit die embedded in an encapsulant and a redistribution structure on the encapsulant. The redistribution structure includes a metallization layer distal from the encapsulant and the integrated circuit die, and a dielectric layer distal from the encapsulant and the integrated circuit die and on the metallization layer. The package structure also includes a first under metallization structure on the dielectric layer and a Surface Mount Device and/or Integrated Passive Device (“SMD/IPD”) attached to the first under metallization structure. The first under metallization structure includes first through fourth extending portions extending through first through fourth openings of the dielectric layer to first through fourth patterns of the metallization layer, respectively. The first opening, the second opening, the third opening, and the fourth opening are physically separated from each other.

BACKGROUND

Semiconductor devices are used in a variety of electronic applications,such as personal computers, cell phones, digital cameras, and otherelectronic equipment, as examples. Semiconductor devices are typicallyfabricated by sequentially depositing insulating or dielectric layers,conductive layers, and semiconductive layers of material over asemiconductor substrate, and patterning the various material layersusing lithography to form circuit components and elements thereon.Dozens or hundreds of integrated circuits are typically manufactured ona single semiconductor wafer. The individual dies are singulated bysawing the integrated circuits along a scribe line. The individual diesare then packaged separately, in multi-chip modules, or in other typesof packaging, for example.

The semiconductor industry continues to improve the integration densityof various electronic components (e.g., transistors, diodes, resistors,capacitors, etc.) by continual reductions in minimum feature size, whichallow more components to be integrated into a given area. These smallerelectronic components such as integrated circuit dies may also requiresmaller packages that utilize less area than packages of the past, insome applications.

BRIEF DESCRIPTION OF THE DRAWINGS

Aspects of the present disclosure are best understood from the followingdetailed description when read with the accompanying figures. It isnoted that, in accordance with the standard practice in the industry,various features are not drawn to scale. In fact, the dimensions of thevarious features may be arbitrarily increased or reduced for clarity ofdiscussion.

FIGS. 1A through 1C are various views of a first structure to attach aSMD and/or IPD (generally, “SMD/IPD”) in accordance with someembodiments.

FIGS. 2A through 2C are various views of a second structure to attach aSMD/IPD in accordance with some embodiments.

FIGS. 3A through 3C are various views of a third structure to attach amulti-terminal SMD/IPD in accordance with some embodiments.

FIGS. 4 through 13 are cross sectional views of intermediate stepsduring a manufacturing process for forming a package in accordance withsome embodiments.

DETAILED DESCRIPTION

The following disclosure provides many different embodiments, orexamples, for implementing different features of the provided subjectmatter. Specific examples of components and arrangements are describedbelow to simplify the present disclosure. These are, of course, merelyexamples and are not intended to be limiting. For example, the formationof a first feature over or on a second feature in the description thatfollows may include embodiments in which the first and second featuresare formed in direct contact, and may also include embodiments in whichadditional features may be formed between the first and second features,such that the first and second features may not be in direct contact. Inaddition, the present disclosure may repeat reference numerals and/orletters in the various examples. This repetition is for the purpose ofsimplicity and clarity and does not in itself dictate a relationshipbetween the various embodiments and/or configurations discussed.

Further, spatially relative terms, such as “beneath,” “below,” “lower,”“above,” “upper” and the like, may be used herein for ease ofdescription to describe one element or feature's relationship to anotherelement(s) or feature(s) as illustrated in the figures. Similarly, termssuch as “front side” and “back side” may be used herein to more easilyidentify various components, and may identify that those components are,for example, on opposing sides of another component. The spatiallyrelative terms are intended to encompass different orientations of thedevice in use or operation in addition to the orientation depicted inthe figures. The apparatus may be otherwise oriented (rotated 90 degreesor at other orientations) and the spatially relative descriptors usedherein may likewise be interpreted accordingly.

Embodiments discussed herein may be discussed in a specific context,namely a Surface Mount Device (SMD) and/or Integrated Passive Device(IPD) attached to a fan-out or fan-in wafer-level package, and variousstructures used to attach a SMD and/or IPD to such a package. Otherembodiments contemplate other applications, such as different packagetypes or different configurations that would be readily apparent to aperson of ordinary skill in the art upon reading this disclosure. Itshould be noted that embodiments discussed herein may not necessarilyillustrate every component or feature that may be present in astructure. For example, multiples of a component may be omitted from afigure, such as when discussion of one of the component may besufficient to convey aspects of the embodiment. Further, methodembodiments discussed herein may be discussed as being performed in aparticular order; however, other method embodiments may be performed inany logical order.

FIGS. 1A through 1C illustrate various views of a structure to attach aSMD and/or IPD (generally, “SMD/IPD”) in accordance with someembodiments. FIG. 1A is a cross-sectional view of a structure on whichan SMD/IPD 54 is attached, and FIGS. 1B and 1C are overlaid layout viewsof respective portions of the structure. FIG. 1B illustrates an overlaidlayout view of section B in FIG. 1A, and FIG. 1C illustrates an overlaidlayout view of section C in FIG. 1A. Cross-section A-A in FIGS. 1B and1C is the cross-sectional view illustrated in FIG. 1A. Example materialsand methods for forming this structure are discussed in the context ofthe manufacturing process of FIGS. 4 through 13, and hence, suchmaterials and processes are omitted here for brevity.

FIG. 1A illustrates a lower metallization layer including a first lowermetallization pattern 40 a and a second lower metallization pattern 40b. Each of the first lower metallization pattern 40 a and the secondlower metallization pattern 40 b can be a line, landing pad, or the likein the lower metallization layer. A lower dielectric layer 42 is overand on the lower metallization layer, including the first lowermetallization pattern 40 a and the second lower metallization pattern 40b.

An upper metallization layer is on the lower dielectric layer 42, andthe upper metallization layer includes a first upper metallizationpattern 44 a with a first via 46 a and includes a second uppermetallization pattern 44 b with a second via 46 b. As illustrated inFIG. 1B (but not specifically in FIG. 1A), the upper metallization layerfurther includes a third upper metallization pattern 44 c and a fourthupper metallization pattern 44 d. In both FIGS. 1A and 1B, the uppermetallization pattern further includes a fifth upper metallizationpattern 44 e. Each of the first upper metallization pattern 44 a, thesecond upper metallization pattern 44 b, the third upper metallizationpattern 44 c, and the fourth upper metallization pattern 44 d can be aline, landing pad, or the like in the upper metallization layer. Thefirst via 46 a extends through the lower dielectric layer 42 and iselectrically and directly mechanically coupled to the first lowermetallization pattern 40 a and the first upper metallization pattern 44a, and the second via 46 b extends through the lower dielectric layer 42and is electrically and directly mechanically coupled to the secondlower metallization pattern 40 b and the second upper metallizationpattern 44 b. A third via 46 c and a fourth via 46 d may extend throughthe lower dielectric layer and be electrically and directly mechanicallycoupled to the third upper metallization pattern 44 c and the fourthupper metallization pattern 44 d, respectively, and a respective lowermetallization pattern. An upper dielectric layer 47 is over and on theupper metallization layer, including the first upper metallizationpattern 44 a and the second upper metallization pattern 44 b.

A first under metallization 50 a is on the upper dielectric layer 47.The first under metallization 50 a includes a first extending portion 48a and a second extending portion 48 b. The first extending portion 48 aextends through the upper dielectric layer 47 and is electrically anddirectly mechanically coupled to the first upper metallization pattern44 a, and the second extending portion 48 b extends through the upperdielectric layer 47 and is electrically and directly mechanicallycoupled to the second upper metallization pattern 44 b. The firstextending portion 48 a and the second extending portion 48 b extend fromthe first under metallization 50 a through separate openings through theupper dielectric layer 47 to the first upper metallization pattern 44 aand the second upper metallization pattern 44 b, respectively. Asillustrated in FIG. 1B (but not specifically in FIG. 1A), a second undermetallization 50 b is on the upper dielectric layer 47 and includes athird extending portion 48 c and a fourth extending portion 48 d. Thethird extending portion 48 c extends through the upper dielectric layer47 and is electrically and directly mechanically coupled to the thirdupper metallization pattern 44 c, and the fourth extending portion 48 dextends through the upper dielectric layer 47 and is electrically anddirectly mechanically coupled to the fourth upper metallization pattern44 d. The third extending portion 48 c and the fourth extending portion48 d extend from the second under metallization 50 b through separateopenings through the upper dielectric layer 47 to the third uppermetallization pattern 44 c and the fourth upper metallization pattern 44d, respectively. Although not specifically illustrated in across-sectional view, the second under metallization 50 b with the thirdextending portion 48 c to the third upper metallization pattern 44 c andwith the fourth extending portion 48 d to the fourth upper metallizationpattern 44 d may have a same or similar cross-section as correspondingcomponents illustrated in FIG. 1A.

As shown in FIG. 1A, the first under metallization 50 a (and similarlythe second under metallization 50 b, although not specificallyillustrated) can have a depression laterally between the first extendingportion 48 a and the second extending portion 48 b. This may result froma degree of planarity of the immediately underlying surface of the upperdielectric layer 47. This surface of the upper dielectric layer 47 mayresult from various physical effects during its formation. For example,a distance between the first upper metallization pattern 44 a and thesecond upper metallization pattern 44 b, without any intervening uppermetallization pattern therebetween, can cause a meniscus effect in thissurface of the upper dielectric layer 47 when the upper dielectric layer47 is spun-on. In other examples, the immediately underlying surface ofthe upper dielectric layer 47 is planar, which can result in nodepression being laterally between the first extending portion 48 a andthe second extending portion 48 b.

A first connector 52 a electrically and directly mechanically connectsthe first under metallization 50 a and a first terminal of a SMD/IPD 54.A second connector 52 b electrically and directly mechanically connectsthe second under metallization 50 b and a second terminal of the SMD/IPD54. The SMD/IPD 54 can be smaller than a typical integrated circuit die(such as integrated circuit die 206 discussed below) and can include oneor more passive device, such as a capacitor, resistor, diode, or thelike, without including an active device, such as a transistor or thelike.

FIG. 1B further illustrates various dimensions of components. An X-axisand a Y-axis are depicted for ease of reference. Reference to anextending portion 48 refers to any of the extending portions 48 a, 48 b,48 c, and 48 d individually. Reference to an upper metallization pattern44 refers to any of the upper metallization patterns 44 a, 44 b, 44 c,and 44 d individually. Reference to an under metallization 50 refers tounder metallizations 50 a and 50 b individually.

The upper metallization pattern 44 has a first x-direction dimension D1xand a first y-direction dimension D1y, which may be equal. The extendingportion 48 has a second x-direction dimension D2x and a secondy-direction dimension D2y, which may be equal. The under metallization50 has a third x-direction dimension D3x and a third y-directiondimension D3y. A fourth x-direction dimension D4x is between the uppermetallization patterns 44 that are connected through respectiveextending portions 48 to a same under metallization 50. A fourthy-direction dimension D4y is between the nearest upper metallizationpatterns 44 that are connected through respective extending portions 48to different under metallizations 50 that are used to attach a sameSMD/IPD 54. A smallest fifth x-direction dimension D5x is between anupper metallization pattern 44 and the fifth upper metallization pattern44 e.

In some embodiments, the under metallization 50 extends laterally beyonda corresponding extending portion 48 in both an x-direction and ay-direction. For example, in FIG. 1B, the under metallization 50 extendslaterally in a y-direction from both y-boundaries of the correspondingextending portion 48, such as by a distance of half of the differencebetween dimension D3y and dimension D2y (i.e.,

$\left. \frac{D_{3y} - D_{2y}}{2} \right).$Further, for example, the under metallization 50 extends laterally in anx-direction from both x-boundaries of the corresponding extendingportion 48, such as by a distance of half of a difference between thedimension D3x and a sum of dimensions D4x, D2x, and D1x (i.e.,

$\left. \frac{D_{3x} - \left( {D_{4x} + D_{2x} + D_{1x}} \right)}{2} \right)$from one x-boundary, and by a distance toward another extending portion48 of the same under metallization 50.

In some embodiments, the upper metallization pattern 44 extendslaterally beyond a corresponding extending portion 48 in both anx-direction and a y-direction. For example, in FIG. 1B, the uppermetallization pattern 44 extends laterally in a y-direction from bothy-boundaries of the corresponding extending portion 48, such as by adistance of half of the difference between dimension D1y and dimensionD2y (i.e.,

$\left. \frac{D_{1y} - D_{2y}}{2} \right).$Further, for example, the upper metallization pattern 44 extendslaterally in an x-direction from both x-boundaries of the correspondingextending portion 48, such as by a distance of half of a differencebetween the dimension D1x and the dimension D2x (i.e.,

$\left. \frac{D_{1x} - D_{2x}}{2} \right).$

In some embodiments, the upper metallization pattern 44 extendslaterally beyond a corresponding under metallization 50 in both anx-direction and a y-direction. For example, in FIG. 1B, the uppermetallization pattern 44 extends laterally in a y-direction from bothy-boundaries of the corresponding under metallization 50, such as by adistance of half of the difference between dimension D1y and dimensionD3y (i.e.,

$\left. \frac{D_{1y} - D_{3y}}{2} \right).$Further, for example, the upper metallization pattern 44 extendslaterally in an x-direction from an x-boundary of the correspondingunder metallization 50, such as by a distance of half of the sum oftwice the dimension D1x and dimension D4x less the dimension D3x (i.e.,

$\left. \frac{\left( {{2D_{1x}} + D_{4x}} \right) - D_{3x}}{2} \right),$and the under metallization 50 extends laterally in an x-direction fromanother x-boundary of the upper metallization pattern 44 to anotherupper metallization pattern 44 to which the under metallization 50 isconnected through an extending portion 48.

In some embodiments, dimension D1x is greater than dimension D2x (i.e.,D_(1x)>D_(2x)). Further in some embodiments, dimension D1y is greaterthan dimension D3y, which is greater than dimension D2y (i.e.,D_(1y)>D_(3y)>D_(2y)). In some embodiments, the dimensions D1x and D1ycan be in a range from about 160 μm to about 300 μm, such as about 255μm. In some embodiments, the dimensions D2x and D2y can be in a rangefrom about 100 μm to about 240 μm, such as about 195 μm. In someembodiments, the dimension D3x can be in a range from about 620 μm toabout 1500 μm, such as about 1000 μm, and the dimension D3y can be in arange from about 130 μm to about 270 μm, such as about 200 μm. In someembodiments, the dimension D4x can be in a range from about 110 μm toabout 1210 μm, such as about 520 μm, and the dimension D4y can be in arange from about 110 μm to about 340 μm, such as about 170 μm. In someembodiments, the dimension D5x can be greater than about 40 μm.

In the illustrated embodiment, the upper metallization pattern 44 andthe extending portion 48 are each square (D_(1x)=D_(1y) andD_(2x)=D_(2y)), and the under metallization 50 is rectangular (e.g.,D_(3x)>D_(3y)). In other embodiments, these components can take ondifferent shapes, such as circular, ovaloid, hexagonal, octagonal, orany other polygonal shape. Further, the dimensions may have differentrelationships.

FIGS. 2A through 2C illustrate various views of a structure to attach aSMD/IPD in accordance with some embodiments. FIG. 2A is across-sectional view of a structure on which an SMD/IPD 54 is attached,and FIGS. 2B and 2C are overlaid layout views of respective portions ofthe structure. FIG. 2B illustrates an overlaid layout view of section Bin FIG. 2A, and FIG. 2C illustrates an overlaid layout view of section Cin FIG. 2A. Cross-section A-A in FIGS. 2B and 2C is the cross-sectionalview illustrated in FIG. 2A. FIGS. 2A through 2C illustrate amodification of the example in FIGS. 1A through 1C, and discussion oflike elements is omitted for brevity.

FIGS. 2A and 2B further illustrate that the upper metallization layerincludes a dummy metallization pattern 62 over the lower dielectriclayer 42. The dummy metallization pattern 62 is between the first uppermetallization pattern 44 a and the second upper metallization pattern 44b, between the first upper metallization pattern 44 a and the thirdupper metallization pattern 44 c, between the second upper metallizationpattern 44 b and the fourth upper metallization pattern 44 d, andbetween the third upper metallization pattern 44 c and the fourth uppermetallization pattern 44 d. As shown in the layout view of FIG. 2B, thedummy metallization pattern 62 forms a cross in which each of the firstupper metallization pattern 44 a, second upper metallization pattern 44b, third upper metallization pattern 44 c, and fourth uppermetallization pattern 44 d is disposed in a separate quadrant. The dummymetallization pattern 62 can be electrically isolated from any otheroperational metallization pattern in the upper metallization layer.

As shown in FIG. 2A, the first under metallization 60 a (and similarlythe second under metallization 60 b, although not specificallyillustrated) can be planar laterally between the first extending portion48 a and the second extending portion 48 b. This may result from adegree of planarity of the immediately underlying surface of the upperdielectric layer 47. The presence of the dummy metallization pattern 62may allow this surface of the upper dielectric layer 47 to be planarbetween the first extending portion 48 a and the second extendingportion 48 b depending on methods of forming the various components.

FIGS. 2A and 2B further illustrate that the dummy metallization pattern62 can have openings 64 through the dummy metallization pattern 62. Theopenings 64 can take any configuration in the dummy metallizationpattern 62. As illustrated, two columns of openings 64 extend along ay-direction, and one row of openings 64 extends along an x-direction.

Each of the openings has a sixth x-direction dimension D6x and a sixthy-direction dimension D6y, which may be equal. A first branch of thedummy metallization pattern 62 extending in a y-direction (with the twocolumns of openings 64) has a seventh x-direction dimension D7x, andanother second branch of the dummy metallization pattern 62 extending inan x-direction (with the one row of openings 64) has a seventhy-direction dimension D7y. The first branch of the dummy metallizationpattern 62 is an eighth x-direction dimension D8x from a neighboringupper metallization pattern 44. The second branch of the dummymetallization pattern 62 is an eighth y-direction dimension D8y from aneighboring upper metallization pattern 44.

In some embodiments, the dimensions D6x and D6y can be in a range fromabout 10 μm to about 50 μm, such as about 30 μm. In some embodiments,the dimension D7x can be in a range from about 30 μm to about 1130 μm,such as about 440 μm, and the dimension D7y can be in a range from about30 μm to about 220 μm, such as about 50 μm. In some embodiments, thedimension D8x can be greater than about 40 μm, such as in a range fromabout 40 μm to about 100 μm, such as about 40 μm, and the dimension D8ycan be greater than about 40 μm, such as in a range from about 40 μm toabout 100 μm, such as about 40 μm.

FIGS. 3A through 3C illustrate various views of a structure to attach amulti-terminal SMD/IPD in accordance with some embodiments. FIG. 3A is across-sectional view of a structure on which an SMD/IPD 84 is attached,and FIGS. 3B and 3C are overlaid layout views of respective portions ofthe structure. FIG. 3B illustrates an overlaid layout view of section Bin FIG. 3A, and FIG. 3C illustrates an overlaid layout view of section Cin FIG. 3A. Cross-section A-A in FIGS. 3B and 3C is the cross-sectionalview illustrated in FIG. 3A. Example materials and methods for formingthis structure are discussed in the context of the manufacturing processof FIGS. 4 through 13, and hence, such materials and processes areomitted here for brevity.

FIG. 3A illustrates a lower metallization layer including a first lowermetallization pattern 70 a, a second lower metallization pattern 70 b, athird lower metallization pattern 70 c, and a fourth lower metallizationpattern 70 d. A lower dielectric layer 72 is over and on the lowermetallization layer, including the lower metallization patterns 70 a, 70b, 70 c, and 70 d.

An upper metallization layer is on the lower dielectric layer 72, andthe upper metallization layer includes a first upper metallizationpattern 74 a with a first via 76 a, a second upper metallization pattern74 b with a second via 76 b, a third upper metallization pattern 74 cwith a third via 76 c, and a fourth upper metallization pattern 74 dwith a fourth via 76 d. As illustrated in FIG. 3B (but not specificallyin FIG. 3A), the upper metallization layer further includes fifththrough twelfth upper metallization patterns 74 e through 74 l. In bothFIGS. 3A and 3B, the upper metallization pattern further includes athirteenth upper metallization pattern 74 m. The first through fourthvias 76 a through 76 d extend through the lower dielectric layer 72 andeach is electrically and directly mechanically coupled to a respectiveone of the first through fourth lower metallization patterns 70 athrough 70 d and a respective one of the first through fourth uppermetallization patterns 74 a through 74 d. An upper dielectric layer 77is over and on the upper metallization layer, including the firstthrough twelfth upper metallization patterns 74 a through 74 l.

A first through twelfth under metallizations 80 a through 80 l are onthe upper dielectric layer 77. The first through twelfth undermetallizations 80 a through 80 l include a respective one of firstthrough twelfth extending portions 78 a through 78 l. The first throughtwelfth extending portions 78 a through 78 l extend through the upperdielectric layer 47 and each is electrically and directly mechanicallycoupled to a respective one of the first through twelfth uppermetallization patterns 74 a through 74 l. The first through twelfthextending portions 78 a through 78 l extend through separate openingsthrough the upper dielectric layer 77 to the respective one of the firstthrough twelfth upper metallization pattern 74 a through 74 l. Althoughnot specifically illustrated in a cross-sectional view, the fifththrough eighth under metallizations 80 e through 80 h with therespective fifth through eighth extending portions 78 e through 78 h tothe respective fifth through eighth upper metallization patterns 74 ethrough 74 h have a same or similar cross-section as correspondingcomponents illustrated in FIG. 3A, and the ninth through twelfth undermetallizations 80 i through 80 l with the respective ninth throughtwelfth extending portions 78 i through 78 l to the respective ninththrough twelfth upper metallization patterns 74 i through 74 l have asame or similar cross-section as corresponding components illustrated inFIG. 3A. First through twelfth connectors 82 a through 82 l electricallyand directly mechanically connect the first through twelfth undermetallizations 80 a through 80 l and first through twelfth terminals ofa SMD/IPD 84, respectively.

As shown in FIGS. 3B and 3C, the multi-terminal SMD/IPD 84 has three ormore terminals. The terminals of the SMD/IPD 84 can be in an array, suchas a 4×3 array as illustrated. Each stack of a respective connector 82,under metallization 80 with extending portion 78, and uppermetallization pattern 74 can correspond to a respective one of theterminals of the SMD/IPD 84, and therefore, those stacks can also bearranged in an array, such as shown. Further, the under metallization80, the extending portion 78, and the upper metallization pattern 74 areshown as having a hexagonal shape, and in other embodiments, thesecomponents can be any shape, such as square, rectangular, circular,ovaloid, hexagonal, or any other polygon. As shown, the undermetallization 80 extends laterally beyond boundaries of the respectiveextending portion 78, and the upper metallization pattern 74 extendslaterally beyond boundaries of the respective under metallization 80.

FIGS. 4 through 13 illustrate an example manufacturing process in whichany of the foregoing structures illustrated in FIGS. 1A through 1C, 2Athrough 2C, and 3A through 3C may be used. The structure of FIGS. 2Athrough 2C is illustrated in this example process for convenience, butany other of the foregoing structures can be formed, as one of ordinaryskill in the art will readily understand. Further, such structures canbe formed on and/or in any substrate, package component, or package, andFIGS. 4 through 13 are provided as an example.

FIGS. 4 through 13 illustrate cross sectional views of intermediatesteps during a manufacturing process for forming a package in accordancewith some embodiments. FIG. 4 illustrates a carrier 200 and a releaselayer 202 formed on the carrier 200. The carrier 200 may be a glasscarrier, a ceramic carrier, or the like. The carrier 200 may be a wafer.The release layer 202 may be formed of a polymer-based material, whichmay be removed along with the carrier 200 from the overlying structuresthat will be formed in subsequent steps. In some embodiments, therelease layer 202 is an epoxy-based thermal-release material, whichloses its adhesive property when heated. In other embodiments, therelease layer 202 may be an ultra-violet (UV) glue, which loses itsadhesive property when exposed to UV lights. The release layer 202 maybe dispensed as a liquid and cured, may be a laminate film laminatedonto the carrier 200, or may be the like. The top surface of the releaselayer 202 may be leveled and may have a high degree of planarity.

In FIG. 5, integrated circuit dies 206 are adhered to the release layer202 by an adhesive 204. Before being adhered to the release layer 202,the integrated circuit dies 206 may be processed according to applicablemanufacturing processes to form integrated circuits in the integratedcircuit dies 206. For example, devices, such as transistors, diodes,capacitors, resistors, etc., may be formed in and/or on a semiconductorsubstrate, such as a semiconductor wafer, and may be interconnected byinterconnect structures formed by, for example, metallization patternsin one or more dielectric layers on the semiconductor substrate to forman integrated circuit. Die connectors 208, such as conductive pillars(for example, comprising a metal such as copper), may be formed exteriorto the integrated circuit dies 206 by, for example, plating to bemechanically and electrically coupled to the respective integratedcircuit dies 206 on what may be referred to as respective active sidesof the integrated circuit dies 206. A dielectric material 210 may beformed over the integrated circuit dies 206 and the die connectors 208,for example, by spin coating, lamination, Chemical Vapor Deposition(CVD), or the like. The adhesive 204 may be applied to a back side ofthe integrated circuit dies 206, such as to a back side of therespective semiconductor wafer. The adhesive 204 may be any suitableadhesive, epoxy, or the like. The integrated circuit dies 206 may besingulated, such as by sawing or dicing, and adhered to the releaselayer 202 by the adhesive 204 using, for example, a pick-and-place tool.

In FIG. 6, an encapsulant 212 is formed encapsulating the integratedcircuit dies 206 on the release layer 202. The encapsulant 212 may be amolding compound, epoxy, or the like, and may be applied by compressionmolding, transfer molding, or the like. After curing, the encapsulant212 may undergo a grinding process to expose die connectors 208. Topsurfaces of the die connectors 208 and encapsulant 212 are co-planarafter the grinding process. In some embodiments, the grinding processcan be omitted if, for example, the die connectors 208 are exposed afterencapsulating the integrated circuit dies 206.

In FIG. 7, a dielectric layer 220 is formed on the encapsulant 212 andthe die connectors 208. In some embodiments, the dielectric layer 220 isformed of a polymer, which may be a photo-sensitive material such aspolybenzoxazole (PBO), polyimide, benzocyclobutene (BCB), or the like,that may be easily patterned using a lithography mask. In otherembodiments, the dielectric layer 220 is formed of a nitride such assilicon nitride; an oxide such as silicon oxide, PhosphoSilicate Glass(PSG), BoroSilicate Glass (BSG), Boron-doped PhosphoSilicate Glass(BPSG), or the like. The dielectric layer 220 may be formed by spincoating, lamination, CVD, the like, or a combination thereof. Thedielectric layer 220 is then patterned to form openings to expose thedie connectors 208. The patterning may be by an acceptable process, suchas by exposing the dielectric layer 220 to light when the dielectriclayer is a photo-sensitive material, or by etching using, for example,an anisotropic etch.

Then, a metallization layer 222 with vias 224 through openings throughthe dielectric layer 220 is formed. A seed layer is formed over thedielectric layer 220 and in openings in the dielectric layer 220. Insome embodiments, the seed layer is a metal layer, which may be a singlelayer or a composite layer comprising a plurality of sub-layers formedof different materials. In some embodiments, the seed layer comprises atitanium layer and a copper layer over the titanium layer. The seedlayer may be formed using, for example, Physical Vapor Deposition (PVD)or the like. A photo resist is formed and patterned on the seed layer.The photo resist may be formed by spin coating or the like and may beexposed to light for patterning. The pattern of the photo resistcorresponds to a pattern of the metallization layer. The patterningforms openings through the photo resist to expose the seed layer. Aconductive material is formed in the openings of the photo resist and onthe exposed portions of the seed layer. The conductive material may beformed by plating, such as electroplating or electroless plating, or thelike. The conductive material may comprise a conductive material, suchas a metal, like copper, titanium, tungsten, aluminum, or the like.Then, the photo resist and portions of the seed layer on which theconductive material is not formed are removed. The photo resist may beremoved by an acceptable ashing or stripping process, such as using anoxygen plasma or the like. Once the photo resist is removed, exposedportions of the seed layer are removed, such as by using an acceptableetching process, such as by wet or dry etching. The remaining portionsof the seed layer and conductive material form the metallization layer222 with vias 224 through the openings through the dielectric layer 220.Hence, the metallization layer 222 is electrically coupled to integratedcircuits on the integrated circuit dies 206.

In FIG. 8, a dielectric layer 226 is formed on the metallization layer222 and the dielectric layer 220 by repeating processes discussed abovewith respect to FIG. 7. Openings are formed through the dielectric layer226 to expose portions of the metallization layer 222. Then, ametallization layer 228 with vias 230 through openings through thedielectric layer 226 is formed by processes discussed above with respectto FIG. 7. Hence, the metallization layer 228 is electrically coupled tothe metallization layer 222.

In FIG. 9, a dielectric layer 232 is formed on the metallization layer228 and the dielectric layer 226 by repeating processes discussed abovewith respect to FIG. 7. Openings are formed through the dielectric layer232 to expose portions of the metallization layer 228. Then, ametallization layer 234 with vias 236 through openings through thedielectric layer 232 is formed by processes discussed above with respectto FIG. 7. Hence, the metallization layer 234 is electrically coupled tothe metallization layer 228.

Region 240 identifies components that can correspond to components inFIGS. 1A through 1C, 2A through 2C, and 3A through 3C. Metallizationlayer 234 can correspond to the upper metallization layer in any ofFIGS. 1A through 1C, 2A through 2C, and 3A through 3C. For example,metallization layer 234 includes a first metallization pattern 242 a anda first metallization pattern 242 b that correspond to first uppermetallization pattern 44 a and second upper metallization pattern 44 b,respectively, in FIG. 2A. Further, the metallization layer 234 includesa dummy metallization pattern 244 that corresponds to dummymetallization pattern 62 in FIG. 2A, and the metallization layer 234includes a third metallization pattern 246 that corresponds to fifthupper metallization pattern 44 e in FIG. 2A.

In some embodiments, some dielectric layers and metallization layers canbe omitted, while in other embodiments, more dielectric layers andmetallization layers may be included.

In FIG. 10, a dielectric layer 250 is formed on the metallization layer234 and the dielectric layer 232 by repeating processes discussed abovewith respect to FIG. 7. A redistribution structure 258 is thus formed,which includes the dielectric layers 220, 226, 232, and 250 and themetallization layer 222, 228, and 234 with vias 224, 230, and 236,respectively. Openings are formed through the dielectric layer 250 toexpose portions of the metallization layer 234. Then, a undermetallizations 252 and 254 are formed on the dielectric layer 250 andthrough openings through the dielectric layer 250 by processes discussedabove with respect to FIG. 7 for forming a metallization layer. Hence,the under metallizations 252 and 254 are electrically coupled to themetallization layer 234. Under metallization 254 corresponds to firstunder metallization 60 a in FIG. 2A.

In FIG. 11, connectors 262 are formed on the under metallizations 254.In some embodiments, the connectors 262 are a solder-containing material(such as a lead-free solder-containing material), and can furtherinclude a flux material. The connectors 262 can be formed on the undermetallizations 254 by using a printing process or the like. SMD/IPDs 264are then placed on the connectors 262, such as by using a pick-and-placetool. The connectors 262 are attached to respective terminals of theSMD/IPDs 264. A flux in the connectors 262 can adhere the SMD/IPDs 264to the under metallizations 254 until a reflow process is performed toreflow solder in the connectors 262 to more permanently attach theSMD/IPDs 264 to the under metallizations 254.

Further, external connectors 260 are formed on the under metallizations252. The external connectors 260 can be, for example, solder, such as aSn—Ag alloy, a Sn—Ag—Cu alloy, or the like, which may further belead-free or lead-containing, formed by a ball drop process, printing,plating, or the like.

In FIG. 12, a carrier de-bonding is performed to detach (de-bond)carrier 200 from the overlying structure. In accordance with someembodiments, the de-bonding includes projecting a light such as a laserlight or an UV light on release layer 202 so that release layer 202decomposes under the heat of the light and carrier 200 can be removed.The structure is then flipped over and placed on a dicing tape 266.Then, a package singulation process, such as by dicing or sawing, isperformed to singulate individual packages.

FIG. 13 illustrates a package 280 as singulated in FIG. 12 and attachedto a substrate 282. The substrate 282 can be a package substrate, suchas a Printed Circuit Board (PCB) or the like. The substrate 282 has bondpads 284 to which external connectors 260 are contacted and reflowed toform an electrical and mechanical connection.

Embodiments can achieve advantages. For example, embodiments accordingto structures discussed above can reduce a stress at an uppermetallization pattern and/or upper dielectric layer. By reducing astress, risk of delamination and/or cracking in the upper dielectriclayer and/or upper metallization pattern may be mitigated. Yield of amanufactured structure can thus be increased.

An embodiment is a package structure. The package structure includes anintegrated circuit die embedded in an encapsulant and a redistributionstructure on the encapsulant and electrically coupled to the integratedcircuit die. The redistribution structure includes a metallization layerdistal from the encapsulant and the integrated circuit die, and adielectric layer distal from the encapsulant and the integrated circuitdie and on the metallization layer. The package structure also includesa first under metallization structure on the dielectric layer and aSurface Mount Device and/or Integrated Passive Device (“SMD/IPD”)attached to the first under metallization structure. The first undermetallization structure includes a first extending portion extendingthrough a first opening of the dielectric layer to a first pattern ofthe metallization layer, a second extending portion extending through asecond opening of the dielectric layer to a second pattern of themetallization layer, a third extending portion extending through a thirdopening of the dielectric layer to a third pattern of the metallizationlayer, and a fourth extending portion extending through a fourth openingof the dielectric layer to a fourth pattern of the metallization layer.The first opening, the second opening, the third opening, and the fourthopening are physically separated from each other.

Another embodiment is a package structure. The package structurecomprises a die comprising an integrated circuit, an encapsulant atleast laterally encapsulating the die, a redistribution structure on andadjoining the encapsulant, a first under-terminal structure, a secondunder-terminal structure, and a Surface Mount Device and/or IntegratedPassive Device (“SMD/IPD”). The redistribution structure comprises adielectric layer on a metallization layer. The first under-terminalstructure comprises a first extending portion extending through a firstopening through the dielectric layer to the metallization layer andcomprises a second extending portion extending through a second openingthrough the dielectric layer to the metallization layer. The secondunder-terminal structure comprises a third extending portion extendingthrough a third opening through the dielectric layer to themetallization layer and comprises a fourth extending portion extendingthrough a fourth opening through the dielectric layer to themetallization layer. The first opening, the second opening, the thirdopening, and the fourth opening are distinct. The SMD/IPD has a firstterminal attached to the first under-terminal structure and a secondterminal attached to the second under-terminal structure.

A further embodiment is a method. The method comprises encapsulating anintegrated circuit die in an encapsulant; forming a redistributionstructure on the encapsulant, the redistribution structure comprising adielectric layer on a first metallization pattern, a secondmetallization pattern, a third metallization pattern, and a fourthmetallization pattern, wherein the first metallization pattern, thesecond metallization pattern, the third metallization pattern, and thefourth metallization pattern are physically separated; forming a firstunder-terminal metallization and a second under-terminal metallizationon the redistribution structure, the first under-terminal metallizationcomprising a first extending portion extending through a first openingof the dielectric layer to the first metallization pattern andcomprising a second extending portion extending through a second openingof the dielectric layer to the second metallization pattern, the secondunder-terminal metallization comprising a third extending portionextending through a third opening of the dielectric layer to the thirdmetallization pattern and comprising a fourth extending portionextending through a fourth opening of the dielectric layer to the fourthmetallization pattern; and attaching a Surface Mount Device and/orIntegrated Passive Device (“SMD/IPD”) to the first under-terminalmetallization and the second under-terminal metallization, a firstterminal of the SMD/IPD being attached to the first under-terminalmetallization, and a second terminal of the SMD/IPD being attached tothe second under-terminal metallization.

The foregoing outlines features of several embodiments so that thoseskilled in the art may better understand the aspects of the presentdisclosure. Those skilled in the art should appreciate that they mayreadily use the present disclosure as a basis for designing or modifyingother processes and structures for carrying out the same purposes and/orachieving the same advantages of the embodiments introduced herein.Those skilled in the art should also realize that such equivalentconstructions do not depart from the spirit and scope of the presentdisclosure, and that they may make various changes, substitutions, andalterations herein without departing from the spirit and scope of thepresent disclosure.

What is claimed is:
 1. A package structure comprising: an integratedcircuit die embedded in an encapsulant; a redistribution structure onthe encapsulant and electrically coupled to the integrated circuit die,the redistribution structure comprising: a metallization layer distalfrom the encapsulant and the integrated circuit die, wherein themetallization layer is an uppermost metallization layer of theredistribution structure, and a dielectric layer on the metallizationlayer, wherein the dielectric layer is an uppermost dielectric layer ofthe redistribution structure; a first under metallization structure onthe dielectric layer, the first under metallization structurecomprising: a first under-terminal metallization including a firstextending portion and a second extending portion, wherein the firstextending portion extends through a first opening of the dielectriclayer to a first pattern of the metallization layer, wherein the secondextending portion extends through a second opening of the dielectriclayer to a second pattern of the metallization layer, wherein the firstunder-terminal metallization further includes a first upper portion onan upper surface of the dielectric layer distal the encapsulant, thefirst upper portion extending continuously from the first extendingportion to the second extending portion; and a second under-terminalmetallization including a third extending portion and a fourth extendingportion, wherein the third extending portion extends through a thirdopening of the dielectric layer to a third pattern of the metallizationlayer, wherein the fourth extending portion extends through a fourthopening of the dielectric layer to a fourth pattern of the metallizationlayer, wherein the second under-terminal metallization further includesa second upper portion on the upper surface of the dielectric layerdistal the encapsulant, the second upper portion extending continuouslyfrom the third extending portion to the fourth extending portion,wherein the first opening, the second opening, the third opening, andthe fourth opening are physically separated from each other; and aSurface Mount Device and/or Integrated Passive Device (SMD/IPD) attachedto the first under metallization structure, wherein the SMD/IPD has afirst connector formed of a first conductive material, wherein the firstconnector physically contacts the first extending portion and the secondextending portion of the first under-terminal metallization, wherein thefirst conductive material extends continuously from the first extendingportion to the second extending portion.
 2. The package structure ofclaim 1 further comprising: a second under metallization structure onthe dielectric layer and extending to the metallization layer; anexternal connector on the second under metallization structure; and apackage substrate electrically and physically connected to the externalconnector.
 3. The package structure of claim 1, wherein the SMD/IPD hasa second connector physically contacting the third extending portion andthe fourth extending portion of the second under-terminal metallization,wherein the second connector of the SMD/IPD extends continuously fromthe third extending portion to the fourth extending portion.
 4. Thepackage structure of claim 3, wherein no pattern of the metallizationlayer is disposed between the first pattern of the metallization layerand the second pattern of the metallization layer, and no pattern of themetallization layer is disposed between the third pattern of themetallization layer and the fourth pattern of the metallization layer,wherein an upper surface of the first upper portion of the firstunder-terminal metallization has a depression.
 5. The package structureof claim 3, wherein the metallization layer further comprises a dummymetallization pattern, a first portion of the dummy metallizationpattern extending in a first direction between the first pattern of themetallization layer and the second pattern of the metallization layerand between the third pattern of the metallization layer and the fourthpattern of the metallization layer, and a second portion of the dummymetallization pattern extending in a second direction between the firstpattern of the metallization layer and the third pattern of themetallization layer and between the second pattern of the metallizationlayer and the fourth pattern of the metallization layer.
 6. The packagestructure of claim 3, wherein the metallization layer further comprisesa dummy metallization pattern in a region defined by respectiveboundaries of the first pattern of the metallization layer, the secondpattern of the metallization layer, the third pattern of themetallization layer, and the fourth pattern of the metallization layer,a plurality of openings being through the dummy metallization pattern.7. The package structure of claim 1, wherein the first connector has awidth equal to a width of the first under-terminal metallization.
 8. Apackage structure comprising: a die comprising an integrated circuit; anencapsulant at least laterally encapsulating the die; a redistributionstructure on the encapsulant, the redistribution structure comprising adielectric layer on a metallization layer; a first under-terminalstructure on the redistribution structure, the first under-terminalstructure comprising a first extending portion extending through a firstopening through the dielectric layer to a first pattern of themetallization layer and comprising a second extending portion extendingthrough a second opening through the dielectric layer to a secondpattern of the metallization layer, the first under-terminal structurefurther comprising a first upper portion disposed on the redistributionstructure and connecting the first extending portion and the secondextending portion; a second under-terminal structure on theredistribution structure, the second under-terminal structure comprisinga third extending portion extending through a third opening through thedielectric layer to a third pattern of the metallization layer andcomprising a fourth extending portion extending through a fourth openingthrough the dielectric layer to a fourth pattern of the metallizationlayer, the second under-terminal structure further comprising a secondupper portion disposed on the redistribution structure and connectingthe third extending portion and the fourth extending portion, whereinthe first opening, the second opening, the third opening, and the fourthopening are distinct; a dummy pattern in the metallization layer andunder the first upper portion of the first under-terminal structure,wherein the dummy pattern is formed of a conductive material and iselectrically isolated from other conductive features of the packagestructure, wherein the first under-terminal structure extends laterallybeyond lateral extents of the dummy pattern; and a Surface Mount Deviceand/or Integrated Passive Device (SMD/IPD) having a first terminalattached to the first under-terminal structure and a second terminalattached to the second under-terminal structure.
 9. The packagestructure of claim 8, wherein the dummy pattern has a plurality ofopenings therethrough.
 10. The package structure of claim 8, wherein thedummy pattern includes: a first portion extending between the firstpattern and the second pattern and between the third pattern and thefourth pattern, and a second portion extending between the first patternand the third pattern and between the second pattern and the fourthpattern.
 11. The package structure of claim 8, wherein: the firstunder-terminal structure extends along a first direction from the firstextending portion to the second extending portion, and the secondunder-terminal structure extends from the third extending portion to thefourth extending portion along a direction parallel to but not on a sameline as the first direction, each of the first under-terminal structureand the second under-terminal structure having a first dimensionparallel to a second direction perpendicular to the first direction,each of the first extending portion, the second extending portion, thethird extending portion, and the fourth extending portion has a seconddimension parallel to the second direction, the first dimension beinggreater than the second dimension, and each of the first pattern, thesecond pattern, the third pattern, and the fourth pattern has a thirddimension parallel to the second direction, the third dimension beinggreater than the first dimension.
 12. The package structure of claim 8,wherein the first pattern, the second pattern, the third pattern and thefourth pattern are spaced apart from one another.
 13. The packagestructure of claim 8, wherein in a top view, a first center of the firstextending portion, a second center of the second extending portion, athird center of the third extending portion, and a fourth center of thefourth extending portion define vertices of a rectangle.
 14. A methodcomprising: encapsulating an integrated circuit die in an encapsulant;forming a redistribution structure on the encapsulant, theredistribution structure comprising a topmost dielectric layer on atopmost metallization layer, wherein the topmost metallization layer hasa first metallization pattern, a second metallization pattern, a thirdmetallization pattern, and a fourth metallization pattern, wherein thefirst metallization pattern, the second metallization pattern, the thirdmetallization pattern, and the fourth metallization pattern arephysically separated; forming a first under-terminal metallization and asecond under-terminal metallization on the redistribution structure, thefirst under-terminal metallization comprising a first extending portionextending through a first opening of the topmost dielectric layer to thefirst metallization pattern and comprising a second extending portionextending through a second opening of the topmost dielectric layer tothe second metallization pattern, the second under-terminalmetallization comprising a third extending portion extending through athird opening of the topmost dielectric layer to the third metallizationpattern and comprising a fourth extending portion extending through afourth opening of the topmost dielectric layer to the fourthmetallization pattern, wherein the first under-terminal metallizationextends continuously along an upper surface of the topmost dielectriclayer from the first extending portion to the second extending portion,wherein the second under-terminal metallization extends continuouslyalong the upper surface of the topmost dielectric layer from the thirdextending portion to the fourth extending portion; and attaching aSurface Mount Device and/or Integrated Passive Device (SMD/IPD) to thefirst under-terminal metallization and the second under-terminalmetallization, a first terminal of the SMD/IPD being attached to thefirst under-terminal metallization, and a second terminal of the SMD/IPDbeing attached to the second under-terminal metallization, wherein thefirst terminal extends continuously from the first extending portion ofthe first under-terminal metallization to the second extending portionof the first under-terminal metallization, wherein a width of the firstterminal is equal to a width of the first under-terminal metallization.15. The method of claim 14, wherein no dummy metallization is formedlaterally between the first metallization pattern, the secondmetallization pattern, the third metallization pattern, and the fourthmetallization pattern.
 16. The method of claim 14, wherein a dummymetallization is formed in the topmost metallization layer and iselectrically isolated, wherein the dummy metallization is laterallybetween the first metallization pattern and the second metallizationpattern, between the third metallization pattern and the fourthmetallization pattern, between the first metallization pattern and thethird metallization pattern, and between the second metallizationpattern and the fourth metallization pattern.
 17. The method of claim16, wherein a plurality of openings are formed through the dummymetallization.
 18. The method of claim 14, wherein each of the firstunder-terminal metallization and the second under-terminal metallizationhas a first dimension measured along a first direction from the firstextending portion to the third extending portion, each of the firstextending portion, the second extending portion, the third extendingportion, and the fourth extending portion has a second dimensionmeasured along the first direction, the first dimension being greaterthan the second dimension, and each of the first metallization pattern,the second metallization pattern, the third metallization pattern, andthe fourth metallization pattern has a third dimension measured alongthe first direction, the third dimension being greater than the firstdimension.
 19. The method of claim 14 further comprising: forming anunder-connector metallization on the redistribution structure, theunder-connector metallization extending through the topmost dielectriclayer; and forming a solder connector on the under-connectormetallization.
 20. The method of claim 14, wherein a width of theencapsulant is a same as a width of the redistribution structure.